At 05.30 hours on 13 March 1943, U-107 attacked the convoy OS-44 190 miles west of Cape Finisterre and reported hits on three ships. In fact, four ships were hit, the Clan Alpine, Marcella, Oporto and Sembilangan.

The Clan Alpine (Master Joseph Henry Crellin) was later scuttled by HMS Scarborough (L 25) (LtCdr E.B. Carnduff, RN) with depth charges. 28 crew members were lost. The master, 56 crew members and nine gunners were picked up by the sloop, transferred to the British steam merchant Pendeen and landed at Gibraltar.